A SUBMAXIMAL STEP TEST OF AEROBIC CAPACITY OVERESTIMATES VO2 IN CAREER FIREFIGHTERS
Andrew Mangan1, Blake Landon1, Ryan Warner1, Davis Hale1, Roger Kollock1, Gabriel Sanders2, Will Peveler3, 1University of Tulsa, Tulsa, Oklahoma; 2Northern Kentucky University, Highland Heights, Kentucky; 3Liberty University, Lynchburg, Virginia
Due to the average duration of fire suppression activities, 20-45 minutes repeated 2-4 times per event, and short rest interval (5-10 minutes), there is a reliance on both aerobic and anaerobic (glycolytic) sources of energy. Several studies have reported that firefighters experience heart rate (HR) close to maximum values and a rapid onset of blood lactate accumulation. The cardiorespiratory workload at such intensities creates a significant risk for safety. An acute cardiac event (ACE) is a risk factor for firefighters with low levels of aerobic capacity. Many municipalities require their career firefighters maintain an aerobic capacity of ≥42 mL/kg/min, however, few require a true measure of aerobic capacity and instead rely on submaximal predictive values. PURPOSE: The purpose of this study was to determine the difference between peak VO2and estimated VO2usinga maximal and submaximal step test of aerobic capacity in career firefighters. METHODS: Following IRB approval, 18career male firefighters(age 35.21±8.38 yrs.) completed both the WFI Stepmill Test(maximal)of Aerobic Capacity on a StairMaster Gauntlet series step ergometer and the Forestry Step Test(submaximal). Each test was administered two weeks apart. The difference between the two tests was determined using a paired sample t-test with the significance level set at .05. Prior to data comparisons, a Kolmogorov-Smirnov test of normality was performed and determined the data to be from a normal distribution (WFIVO2: p= .20, Forestry VO2: p= .20).RESULTS: Results from the paired sample t-test indicate a significant difference between the WFI VO2and the Foresty Step Test VO2(WFI: 38.08±6.2 vs Forestry: 43.83±6.8, p= .015). In addition, a post hoc comparison using Cohen’s d indicated a large effect size (.882).CONCLUSION: Results of the current study indicate the Forestry Step Test significantly overestimates VO2 in career fighters by 5.75 mL/kg/min. Such tests of aerobic capacity should be used with caution when determining the aerobic capacity in career firefighters.
ACKNOWLEDGEMENTS: This study was funded by The Oklahoma Center for Advancement of Science and Technology Health Research Grant Program and The University of Tulsa Undergraduate Research Challenge Program.
Mangan, A; Landon, B; Warner, R; Hale, D; Kollock, R; Sanders, G; and Peveler, W
"A SUBMAXIMAL STEP TEST OF AEROBIC CAPACITY OVERESTIMATES VO2 IN CAREER FIREFIGHTERS,"
International Journal of Exercise Science: Conference Proceedings: Vol. 11:
7, Article 4.
Available at: https://digitalcommons.wku.edu/ijesab/vol11/iss7/4